Asynchronous (Asn) UVC-treated (+UVC, 5 J/m2, 1 h post-treatment), G1/S transition or S phase synchronized HeLa S3 cells stably expressing eGFP-Cdc45 were lysed and normalized for protein content and separated by gel filtration chromatography analysed by western blotting using antibodies raised against Cdc45, Mcm5 and RPA 32. (panels a, b, c, and d, respectively). Theoretical molecular weight (kDa) and Stoke's radius (Å) of protein standards are overlayed. RPA32 acts as a marker for DNA damage response following UVC treatment. FACS analysis is provided for asynchronous (Asn), G1/S transition and S phase synchronized cells (e) and asynchronous cells treated with 5 J/m2, 1 h post-treatment (f).